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<div class="titlepage"><div><div><h4 class="title">
<a name="phoenix.modules.statement.switch__statement"></a><a class="link" href="switch__statement.html" title="switch_ Statement">switch_
        Statement</a>
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<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">phoenix</span><span class="special">/</span><span class="identifier">statement</span><span class="special">/</span><span class="keyword">switch</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<p>
          The syntax is:
        </p>
<pre class="programlisting"><span class="identifier">switch_</span><span class="special">(</span><span class="identifier">integral_expression</span><span class="special">)</span>
<span class="special">[</span>
    <span class="identifier">case_</span><span class="special">&lt;</span><span class="identifier">integral_value</span><span class="special">&gt;(</span><span class="identifier">sequenced_statements</span><span class="special">),</span>
    <span class="special">...</span>
    <span class="identifier">default_</span><span class="special">(</span><span class="identifier">sequenced_statements</span><span class="special">)</span>
<span class="special">]</span>
</pre>
<p>
          A comma separated list of cases, and an optional default can be provided.
          Note unlike a normal switch statement, cases do not fall through.
        </p>
<p>
          Example: This code prints out <code class="computeroutput"><span class="string">"one"</span></code>,
          <code class="computeroutput"><span class="string">"two"</span></code> or <code class="computeroutput"><span class="string">"other value"</span></code> depending on the
          element's actual value:
        </p>
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">for_each</span><span class="special">(</span><span class="identifier">c</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">c</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span>
    <span class="identifier">switch_</span><span class="special">(</span><span class="identifier">arg1</span><span class="special">)</span>
    <span class="special">[</span>
        <span class="identifier">case_</span><span class="special">&lt;</span><span class="number">1</span><span class="special">&gt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">val</span><span class="special">(</span><span class="string">"one"</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="char">'\n'</span><span class="special">),</span>
        <span class="identifier">case_</span><span class="special">&lt;</span><span class="number">2</span><span class="special">&gt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">val</span><span class="special">(</span><span class="string">"two"</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="char">'\n'</span><span class="special">),</span>
        <span class="identifier">default_</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">val</span><span class="special">(</span><span class="string">"other value"</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="char">'\n'</span><span class="special">)</span>
    <span class="special">]</span>
<span class="special">);</span>
</pre>
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<td align="right"><div class="copyright-footer">Copyright © 2002-2005, 2010, 2014, 2015 Joel de Guzman, Dan Marsden, Thomas
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